The final week of tennis' busiest month in terms of events concludes with nine of the ATP World Tour's top-10 ranked players scheduled for action. No. 1 Andy Murray, No. 2 Novak Djokovic, No. 6 Rafael Nadal and No. 9 Roger Federer are featured in two 500-level tournaments, in Dubai and Acapulco. The women are also in Acapulco, as well as Malaysia. Here's what else we're watching for this week in professional tennis:

Storylines: The 25th anniversary of this event has three Grand Slam singles titlists (24 championships all told). This is the first time we've laid eyes on the 35-year-old Federer since he won the Australian Open, and it will be interesting to see if his upper leg strain remains any kind of issue. Federer is a seven-time winner here and has a winning streak of 10 matches.

The No. 1-ranked Murray, too, is also making his first appearance since Melbourne, where he was ousted in the fourth round. Last year, Wawrinka, who lost to Federer in the Australian Open semifinals, returned to Dubai for the first time since 2008 and won the title, beating Marcos Baghdatis in a straight-sets final.

Of note: Philipp Kohlschreiber, the No. 2 German, needs three match wins to reach the milestone of 400. He reached the semifinals here in 2014.

Storylines: All eyes will be on Djokovic, who makes his tournament debut after accepting a wild card into this event. His last appearance: a stunning second-round upset loss to Denis Istomin at the Australian Open, where he was the two-time defending champion. Nadal, who lost to Federer in the Australian Open final, is a two-time Acapulco champion (and 10-0) and seeks his 70th ATP title. Thiem is coming off Sunday's win in Rio Open and will try to defend last year's career-breakthrough championship run. The 23-year-old Austrian was the youngest player to finish in last year's top 10.

Lucic-Baroni, 34, was a surprise semifinalist in Melbourne before losing to eventual champion Serena Williams. Mladenovic was a recent winner in Saint Petersburg. Puig, the reigning Olympic gold medalist and former Wimbledon runner-up Bouchard add some marquee power to the draw.

Of note: Sock, the Delray Beach winner by walkover Sunday, is also in the field along with Juan Martin del Potro -- who could play Djokovic in his second match.

Brasil Open, Sao Paulo, Brazil (outdoor clay)

Pablo Cuevas will try to defend his Brasil Open championship this week. Matthew Stockman/Getty Images

Storylines: Five top-50 players are in the lineup, including No. 30 Pablo Cuevas and Rio finalist Carreno Busta. Cuevas (2015-16) and Federico Delbonis (2014) are both former champions. Carreno Busta is a top seed in an ATP event for the first time in his career.

Of note: Eighteen-year-old Christian Ruud of Norway is the youngest player in the field. He reached the semifinal in Rio, losing to Carreno Busta.

Alya WTA Malaysian Open, Kuala Lumpur, Malaysia (outdoor hard)

Elina Svitolina is coming off a title at the Dubai Championships, which included a win against Angelique Kerber in the semifinals. Karim Sahib/Getty Images